1. Field of the Invention
The invention concerns an electronic module for electrical voltage conversion that is intended to supply a light source of a headlight, in particular for a motor vehicle.
2. Description of the Related Art
In the automobile industry, use is being made more and more of headlights equipped with discharge lamps, such as xenon lamps, in particular to make them bright and for their longevity.
This type of lamp requires a high-voltage alternating electrical current supply. To control the supply of electric current to the lamp, the headlight comprises an electrical supply device that is equipped with a conversion electronic module, normally referred to as “ballast”, which supplies, from a battery voltage of the motor vehicle, high alternating voltages that are adapted to the type of discharge lamp used.
Discharge lamps may emit a large quantity of electromagnetic radiation, the effect of which is undesirable both on the safety of operation of the other electronic circuits of the vehicle and on the radio environment in which the vehicle is travelling.
To remedy this drawback, it is known how to take several so called “EMC” measures, an acronym meaning “electromagnetic compatibility”, separately or in combination according to circumstances, when the electrical supply device of the discharge lamp of the headlight is designed.
According to a first measure, it is known that some of the electromagnetic radiation is emitted by the ballast and by its connectors. This first measure for reducing the electromagnetic radiation emissions consists, as is known, of executing a shielding of the ballast and its connectors.
According to a second measure, the shieldings must be connected to a common reference electrical potential so that the various shieldings cannot vary in terms of voltage during use and thus change into parasitic radiating structures.
It is thus known how to equip the ballast with a shielding housing. Likewise, the connectors are equipped with a shielding jacket.
According to a known design, the housing and the jacket of the connector are electrically connected to the reference potential by means of a reference track of a printed circuit card of the ballast.
In this known design, the printed circuit card is fixed to the bottom of the housing by means of a fixing stud. This same fixing stud is also in electrical contact with the reference track in order to electrically connect the housing with the reference potential.
In this known design, the connector is fixed to the printed circuit card by lugs that pass through the card. The bottom end of these lugs, which is arranged under the printed circuit card, is conformed as a grapnel which, once twisted around the axis of the lugs, makes it possible to fix the connector to the printed circuit card. These same lugs are in electrical contact the jacket on the one hand and with the reference track on the other hand. Thus the jacket is electrically connected to the reference track by means of the lugs.
The method of producing the ballast comprises an operation of positioning the connector on the printed circuit card, and then an operation of fixing the connector. The lugs of the connector must then be soldered against the reference track of the printed circuit card, during a soldering operation, in order to provide permanent electrical contact. Finally, the printed circuit is positioned at the bottom of the housing during a positioning operation and then fixed during a fixing operation.
However, producing such a ballast is very expensive and requires many operations.
In addition, the operation of fixing the connector is complex to automate.